Maximising the Value of Biosolids - Catchment and Estuary Restoration The Ellen Brook Sustainability Project

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1 Maximising the Value of Biosolids - Catchment and Estuary Restoration The Ellen Brook Sustainability Project Robert Humphries 1, Tom Long 1, Katrina Walton 2 and David Allen 3 1 Water Corporation of Western Australia 2 Chemistry Centre of Western Australia 3 MBS Environmental Riversymposium Perth 13 October 2010

2 Context Swan Estuary Algal Blooms, Climate Change, Resource Efficiency Water Corporation spends ~$3 million/year delivering biosolids to end users who pay nothing for the nutrients and other valuable components Farmers are wasting money and harming the Swan River by using technically inefficient, soluble fertilisers. Climate change is here - farming systems must change to adapt. Resource constraints are real we need to close the loop and recover value from our waste streams.

3 Why Target Ellen Brook? The 716 km 2 Ellen Brook catchment contributes: ~24% of average annual streamflow to Swan Estuary ~43% of the average annual nitrogen load ~55% of the average annual phosphorus load Yet Ellen Brook catchment is only 0.6% of the Swan- Avon catchment area (122,000 km 2 ), making it a key target for intervention. Donohue, R., Deeley, D., Parson, G., Youngs, L. (1994). Estimates of nutrient loads in the Swan-Canning catchment Report No. 13 Swan River Trust, Perth, WA, 24pp.

4 Sustainability Project Approach Develop a cheap, safe slow nutrient release fertiliser & soil improver based on lime-amended biosolids to improve soils and farming in Ellen Brook, and: Create sustainable solutions: Nutrient offsets and carbon credits for Water Corporation Reduced biosolids transport costs and income Improved environmental outcomes Improved farmer incomes; reduced input costs & nutrient wastage. Reduced vulnerability to drying climate, re-balance hydrology Partnerships, enhanced reputation Create an accessible, transparent Governance and data management system All land owner and site details Shared Land Information Platform (SLIP) Monitors performance, carbon sequestration, nutrient leaching Individually designed farm improvement plans (incl. nutrient reduction) With landowner and land manager Based on field data and land owner s plans Secured by simple, common law contract

5 Lime-amended BioClay or LaBC What is in LaBC? 30% Lime-amended d Biosolids (LAB) & 70% clay 70.00% And NO pathogens! 60.00% 50.00% 00% 40.00% 30.00% 20.00% 10.00% 0.00% Calcium Oxide 3% Cellulose & Lignin 6% Moisture 27% Kaolin Clay 64%

6 Large-scale Blending of LaBC is Difficult Derelict Coal Screener November 2009, Kwinana Landfill Site From this..

7 To this! All for $40,000! 000!

8 The Making of Lime-amended BioClay (LaBC ) < 1. Clay stockpile (1.5 million tonnes!) 2. Lime-amended Biosolids (LAB) delivery> < 3. Trommel to blend LAB with clay to make LaBC 4. Stockpiled LaBC for curing >

9 LaBC applied at a rate of 50 wet tonnes per hectare provides: Effective amelioration of existing soil acidity, countering soil acidity for several years, and removing the need to apply agricultural lime. Adequate phosphorus for at least 4-7 years. Sufficient copper and zinc for at years. A improvement in the wettability of severely hydrophobic h soils. An improvement in soil water holding capacity and nutrient retention. Probably inadequate potassium for more than one year. Sufficient nitrogen, sulphur and manganese for one to five years. Excellent growth of oats, perennial grasses and farm trees.

10 LaBC Significantly Reduces Soil Water Repellence Water Repellency MED WDPT MED (M) WD DPT (secon nds) Application Rate (dry tonnes of LaBC per hectare 0

11 Phosphorus Retention Index (PRI) of LaBC and LAB PRI PRI (ml/g) LaBC LAB Application Rate (tonnes LAB equiv/ha)

12 LaBC metals all below Class 1 standard level LaBC Metals and Metalloids - Percent of Maximum Class 1 Permitted Concentration LaBC Metals % Class 1 Standard Arsenic Barium Boron Cadmium Chromium total Cobalt Copper Lead Manganese Mercury Molybdenum Nickel Selenium Tin Vanadium Zinc

13 Growth Response Trials 2009 West Road Bullsbrook 300 kg/ha Super 3:1 200 tonnes/ha LaBC 50 kg/ha Urea No LaBC

14 West Road Bullsbrook Field Trial 2009 Super 3:1 vs. LaBC First Year Oats Ovens, R (2009). Report on LaBC field trial to Water Corporation. Department of Agriculture and Food, December 2009.

15 Professor Stephen R. Smith of Imperial College London, writes Improving the acceptability of biosolids in the way described here, by defining a careful product specification supported by a thorough quality assurance system and that provides clearly defined economic and environmental benefits to support longterm sustainability is an approach that should be encouraged to underpin the development and expansion of recycling initiatives for biosolids in the future. This may be regarded as best practice in the biosolids industry and, in the UK, LABC would probably bl be a candidate dd for assessment for its suitability bl at meeting end-of-waste criteria for full recovery as a product under the revised European Waste Framework Directive.

16 In Summary, More Sustainable Outcomes Environmental - Carbon fixation - Nutrient leaching - Biodiversity - Water quality Improved Sustainability Economic - Farmer incomes - Local employment - Reuse of waste - Revenue Costs Social - Relationships - Cooperation - Climate resilience - Social resilience Technical - Low leach nutrients - Non-wetting soils - Soil water capacity - Perennial plants

17 Our Partners Department of Defence access to land for field at Bullsbrook; future reforestation projects ChemCentre WA leaching column and field lysimeter studies Department of Agriculture and Food Shared Land Information o Platform (SLIP); agronomic o advice; Forest Products Commission farm forestry Swan River Trust Ellen Brook WQIP; nutrient offsets scheme? Perth Region NRM catchment community liaison Commonwealth Government Caring for Our Country funding. Faculty of Earth and Environment, University of Western Australia - soil carbon research & monitoring CSBP fertiliser advice. Biosolids regulators - Department of Environment & Conservation, Department of Health.